R3721-F3210-F3171-HP High-End Firewalls Network Management Configuration Guide-6PW101

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NOTE:
• The hello and dead intervals restore to default values after you chan
g
e the network type for an interface.
• The dead interval should be at least four times the hello interval on an interface.
• The poll interval is at least four times the hello interval.
• The retransmission interval should not be so small to avoid unnecessary LSA retransmissions. In
g
eneral,
this value is bigger than the round-trip time of a packet between two neighbors.
Specifying LSA transmission delay
Each LSA in the LSDB has an age that is incremented by 1 every second, but the age does not change
during transmission. It is necessary to add a transmission delay into the age time especially for low
speed links.
To specify the LSA transmission delay on an interface:
Ste
p
Command Remarks
1. Enter system view. system-view N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Specify the LSA transmission
delay.
ospf trans-delay seconds
Optional.
1 second by default.
Specifying SPF calculation interval
LSDB changes lead to SPF calculations. When the topology changes frequently, a large amount of
network and router resources are occupied by SPF calculation. You can adjust the SPF calculation
interval to reduce the impact.
To configure SPF calculation interval:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter OSPF view.
ospf [ process-id | router-id router-id
| vpn-instance vpn-instance-name ] *
N/A
3. Specify the SPF calculation
interval.
spf-schedule-interval
maximum-interval [ minimum-interval
[ incremental-interval ] ]
Optional.
By default, the interval is 5
seconds.
NOTE:
W
hen network changes are not frequent, the minimum-interval is adopted. If network changes become
frequent, the SPF calculation interval is incremented by
incremental-interval × 2
n-2
(n is the number of
calculation times) each time a calculation occurs until the
maximum-interval is reached.
Specifying the LSA arrival interval
After receiving the same LSA as the previously received LSA within the LSA arrival interval, OSPF discards
the LSA.
To configure the LSA arrival interval: